When an upload failed with a retryable error the pacer retried the
whole PUT with the same input stream. The stream had already been
consumed by the first attempt so the retry uploaded an empty file.
This fixes it by using CallNoRetry for the upload, as the other
backends do, so retryable errors are returned wrapped in a RetryError
for the caller to retry the upload with a fresh stream.
The objects returned from Put, Move and Update kept the caller's full
nanosecond precision modtime (which write responses echo back) while
the server stores millisecond precision, so until the object was
re-read the modtime did not match what a fresh listing would report.
Update also discarded the upload response so the object had no SHA256
checksum until re-read. This broke wrappers which compare exact
modtimes and hashes, such as the hasher backend's fingerprint and the
VFS cache. Truncate the modtime to millisecond precision to match
what the server stores and populate the object from the upload
response.
Nick Craig-Wood
FornaxandGitHub